The present invention relates to a system for synchronizing multiple linear actuators, and more particularly to a system for synchronizing multiple slide assemblies of a slide-out room of a vehicle.
Various motorized and towable vehicles are known which have rooms or portions thereof that can be moved in an extended or retracted manner, in order to provide more internal useable space. In a typical structure shown in U.S. Pat. No. 5,785,373 to Futrell et al., one portion of a room is moveable and telescopingly received within the body of mobile vehicle. Similar structures can be used effectively in buildings, although for convenience, the discussion below focuses primarily on the vehicle examples.
Recreational vehicles have become extremely popular in recent years, and because of this popularity, a desire was needed for more livable space within these vehicles. Recreational vehicles are provided with extendable/retractable rooms for increasing the vehicle""s livable space as shown in U.S. Pat. No. 5,634,683 to Young and U.S. Pat. No. 3,572,809 to Buland. The slide-out room is typically extended for use when the vehicle is parked and retracted in a telescoping manner when the vehicle is to be moved. Prior slide-out rooms have been extended and retracted by several actuating systems know in the art, such as linear actuators (hydraulic cylinders) as shown in U.S. Pat. No. RE 32,262 to Stewart, drive screws as shown in U.S. Pat. No. 5, 237,782 to Cooper, and chain mechanisms as shown in U.S. Pat. No. 5,997,074 to Alexander.
Actuating systems can utilize either single or multiple power inputs. The actuating systems typically operate on either a lower portion of the slide-out room adjacent to the floor, or an upper portion of the slide-out room adjacent to its roof. Multiple power input systems have been presented in an effort to eliminate excess mechanical wind-up that exists in single power input systems that link multiple actuators together. Additionally, multiple power input systems have been presented to reduce the use of any cross shafts or hydraulic lines. This provides for added space for such improvements such as storage, larger living space within the slide-out room and the like.
However, prior art actuating systems for slide-out rooms whether using single or multiple power input systems have suffered from continuing deficiencies. For example, it has been difficult to properly seal the slide-out room with the body of the recreational vehicle because both sides of a slide-out room seldom extend/retract perfectly flush with respect to the body of the recreational vehicle. Also, do to inaccuracies in the manufacturing process, a slide-out room maybe xe2x80x9cout of squarexe2x80x9d (a condition when both sides of the room do not meet the front of the room at 90 degrees). Also, in the prior art, it was difficult to extend/retract the actuators at the same speed, causing one actuator to often be extended/retracted further than the other. This causes misalignment in the slide-out room, resulting in the slide-out room being jammed during the extension/retraction of the slide out room.
Therefore, there is presently a desire in the recreational vehicle industry to provide a system that extends/retracts a slide-out room without the deficiencies discussed above.
In accordance with the present invention, a system is provided to address the deficiencies in the prior art. Specifically, a system is provided that synchronizes multiple actuators so that the slide-out room has accurate alignment during extension/retraction, and allows for proper sealing at full extension/retraction.
In accordance to an aspect of the present invention, a system is provided for synchronizing the operation of multiple actuators used to extend and retract a slide-out room of a vehicle. The system comprises a plurality of first members connectable to a chassis of the vehicle. A plurality of second members are attachable to the slide-out room. The second members are operably connected to and slidable within the first members. The system further comprises a synchronization sub-system where the synchronization sub-system operates to monitor and adjust the distance of travel of the second members with respect to the first members so as to enable the second members to extend or retract to a completed position.
In accordance to another aspect of the present invention, a slide-out room assembly is provided that comprises a slide-out room and at least two slide assemblies. Each slide assembly comprising a first slide member attachable to the vehicle and a second slide member operably connected to the slide-out room. The two slide members configured to slidably engage each other to extend and retract the slide assembly. The assembly also comprises a powered actuator for each slide assembly to move the first and second slide members of each slide assembly relative to each other. The assembly further comprises a synchronization system that is in communication with the powered actuators to monitor and control the operation of the powered actuator to cause the slide assemblies to extend and retract in unison.
In accordance with yet another aspect of the present invention, a system is provided for synchronizing the extension and retraction of a slide-out room of a vehicle. The system comprises a pair of slide assemblies. Each slide assembly comprising an outer tube member, and an inner tube member connectable to the slide-out room. The inner tube member is moveable to linearly translate within the outer tube member to extend and retract the slide-out room. The system further comprises a synchronization sub-system which comprises a controller. and an encoder assembly coupled to each slide assembly. The encoder assembly is in electrical communication with the controller. The synchronization sub-system operates to monitor and control the extension and retraction of the slide-out room.
In accordance to still yet another aspect of the present invention, a method is provided for synchronizing the operation of multiple actuators. The method comprises of activating the extension or retraction of the multiple actuators, monitoring the extension or retraction of the multiple actuators, and synchronizing the extension or retraction of the multiple actuators so as to cause the multiple actuators to extend and retract in unison.